973
FXUS65 KGJT 242342
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
542 PM MDT Sun Aug 24 2025

.KEY MESSAGES...

- Convection continues this evening. Storms will be capable of
  producing frequent lightning and heavy rain.

- There is increased concern for flash flooding and debris
  flows in sensitive areas, especially over recent burn scars,
  through mid week.

- Precipitation chances and below normal temperatures continue
  through the seven-day forecast.

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 332 PM MDT Sun Aug 24 2025

As moisture advection continues across eastern Utah and western
Colorado this evening, showers additional rounds of showers and
storms are likely. There might be enough instability left over
across parts of eastern Utah for a couple of stronger updrafts
with satellite imagery showing areas of clearing, but with a
lack of shear to work with storms will continue to be pulsey.
Heavy downpours and frequent lightning are possible with storms
that develop later today.

Scattered to overcast clouds remain in place across much of the
region overnight with light showers possible as well. We`ll be
watching to see if any portions of the forecast area are able to
clear out long enough to build some extra instability tomorrow
morning. If so, we could see a few stronger storms upon
initiation late tomorrow morning that will be capable of
producing hail up to 1" and heavy rain. However, most areas will
stay somewhat insulated from morning heating according to the
HREF. The CAMs favor the eastern Uintas and San Juans for
widespread storms Monday afternoon with scattered showers and
storms elsewhere. Our biggest concern tomorrow continues to be
burn scar flash flooding and debris flows.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 332 PM MDT Sun Aug 24 2025

Flow wrapping around the high to our south brings a persistence
to this wet pattern throughout the week. Tuesday and Wednesday
mark the two days with the strongest precipitation potential of
the long-term period with PoP`s exceeding 60% region-wide both
days. The messaging regarding storm mode remains the same during
this stretch with morning cloud cover heavily dictating if we
will see more convective or stratiform type storms. With us
being deep in the plume of strong moisture, cloud cover is
certainly looking to be more stubborn and lingering throughout
the morning. This is leading us to feel more confident in
widespread stratiform precipitation with pockets of clearing in
cloud cover potentially leading to a few stronger convective
cells. Where clearing may take place, and resulting convective
storms, will be difficult to pinpoint, especially this far in
advance without the CAM guidance.

On Thursday, ridging building over eastern Montana and Wyoming
will begin to pull the anomalous moisture northwards, beginning
a steady drying out across the CWA. This shift in pattern
doesn`t signify a sudden end to these wetting rains though as
near- to above-normal PWAT`s hang around our region at least
into the weekend. However, we will see PoP`s steadily decrease,
reaching a modest 25-35% across primarily higher elevations by
Saturday. Next Monday and beyond, ensembles are in okay
agreement regarding the development of a powerful trough along
the west coast and deep ridging centered along the Rockies. It`s
too soon to speculate how this pattern will impact us though.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 542 PM MDT Sun Aug 24 2025

Volatile atmosphere remains in place with plenty of fuel to
keep thunderstorms and showers going at times over the next 24
hours. Overall confidence is low after 4-6 hours on exact
placement of these showers and storms and expect amendments to
be coming. The main threat will be heavy rain...lightning and
occasional gusts to 40 mph. The bulk of the forecast keeps VFR
prevailing but if a stronger cell moves over the airfield MVFR
conditions will be possible...again probability like confidence
is low (<30%). Calmer conditions through the mid morning hours
will again lead to another round of stronger storms through the
PM hours tomorrow.

&&

.HYDROLOGY...
Issued at 332 PM MDT Sun Aug 24 2025

Aside from daily chances for burn scar flash flooding and
debris flows, we are beginning to monitor an influx of moisture
from the south/southwest on Tuesday. An early look at the CAMs
and model QPF is boosting our confidence for the potential of
flash flooding across southwest Colorado. If these trends hold,
a Flash Flood Watch may be needed.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...None.
UT...None.

&&

$$

SHORT TERM...KAA
LONG TERM...BW
AVIATION...TGJT
HYDROLOGY...KAA